11th April 2020
Can we even expect to get immunity from SARS-CoV 2 after recovery from infection?
This is one of the most challenging topics. (This is a placeholder post)
In my latest article I’ve said:
The second worst-case eventuality we should prepare for is that people will only develop imperfect immunity after recovering from the infection. A number of reports are now showing that people might get re-infected, although that is not too common. But humans do manage to develop a reasonable level of immunity against the four other (common) coronaviruses. If one is infected by one of them, one’s prospects of getting it again are greatly reduced. This suggests that it is reasonable to assume that while a vaccine for SARS-CoV-2 is close to impossible, herd immunity through infection – although challenging – is still largely viable.
The answer is now CONCLUSIVE: People DO develop immunity – and on quite a large scale – see Blood tests show 14% of people are now immune to covid-19 in one town in Germany
This German study is a game changer – just 0.37% death rate + massive immunity already https://t.co/WJ07HuZgJ2
— Sanjeev Sabhlok (@sabhlok) April 11, 2020
PROBLEM SOMEONE SENT ME
We found very limited evidence on immunity after infection with SARS-CoV-2. One study on rhesus macaque monkeys suggests that primary infection with SARS-CoV-2 may protect against reinfection. The study was small and did not provide any information on the duration of immunity. Two studies showed sustainable IgG levels one to two years after SARS-CoV infection, but it is uncertain whether this finding is generalisable to SARS-CoV-2, and also whether sustained levels of antibodies provide full protection against reinfection.
Immunity and protection against reinfection
We did not identify any human studies directly addressing whether infection with SARS- CoV-2 results in immunity and protection against re-infection. Results from a study on rhesus macaque monkeys suggest protection against reinfection after primary infection, but the study was small and did not provide any information on the potential duration of immunity. Results from two studies of antibody levels after infection with SARS-CoV, a similar corona virus, suggest that high levels of IgG may last for up to 1-2 years after infection (18, 19). However, due to the recent identification of the SARS- CoV-2 virus, there are no studies available that can confirm or refute whether this is the case also for SARS-CoV-2. Even if it is likely that sustained levels of antibodies are related to some level of protection against reinfection, we do not at present know if they ensure full protection against reinfection by the same virus or may result in less severe infection at future exposure to the virus.